Domestic appliance with spin acceleration control means



Oct. 26, 1965 c. K. BILLINGS ETAL 3,214,565

DOMESTIC APPLIANCE WITH kSPIN ACCELERATION CONTROL MEANS Original Filed Jan. 19, 1959 4 Sheets-Sheet 1 Daz: ld E alexander mfr/m11 c; Harrold w 5y lM ./.2

. THEIR RTT [Y Ocf- 26, 1965 c. K'. BILLINGS ETAL 3,214,665

DOMESTIC APPLIANCE WITH SPIN ACCELERATION CONTROL MEANS Original Filed Jan. 19. 1959 4 Sheets-Sheet 2 THEIR ATTOR Y C. K. BlLLlNGS ETAL DOMESTIC APPLIANCE WITH SPIN ACCELERATION CONTROL MEANS Original Filed Jan. 19, 1959 4 Sheets-Sheet 3 Donald )7202321422 C Harrod THE/R ATTRNE Oct 26, 1965 c. K. BILLINGs ETAL 3,214,655

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United States Patent O 3,214,665 DOMESTIC APPLIANCE WITH SPIN ACCELERA- TIGN CNTROL MEANS Charles K. Billings, Bellbrook, and Donald F. Alexander and Marshall C. Harrold, Dayton, Ohio, assignors to General Motors Corporation, Detroit, Mich., a corporation of Delaware Original application Jan. 19, 1959, Ser. No. 787,762, now Patent No. 3,078,700, dated Feb. 26, 1963. Divided and this application Sept. 22, 1960, Ser. No. 57,717

7 Claims. (Cl. S18- 224) This invention relates to a domestic appliance and more particularly to an improved operational cycle for a clothes washing machine and is a division of our copending application Ser. No. 787,762, tiled January 19, 1959, now Patent 3,078,700 issued February 26, 1963.

With the progress that is being made in the development of manemade fabrics, it has become evident that standard washing procedures are no longer wholly adequate to the task. In particular it has been found that spinning or centrifuging water from such fabrics tends to set-in wrinkles which are extremely difficult to remove. The wrinkling which occurs to such fabrics is due primarily to the temperatures at which the fabrics are spun. Since the end temperature of the water and clothes before spinning is vitally important to doing a satisfactory job of washing wash-and-wear garments without inducing objectionable wrinkles, it is the purpose of this invention to thermostatically control the spinning mechanism so that centrifuging will be accomplished only when the fabric to be centrifuged is at an acceptable temperature.

The advancement of the washing machine art has also been directed to multi-speed mechanisms wherein the centrifuging or spinning operation is accomplished at more than one speed and wherein different gear ratios ars provided for the different speeds. Since one motor is utilized to spin the tub at the selected speeds, it is desirable to use a circuit design which will permit the use of a motor which is inexpensive and dependable. The most severe task which the motor is called on to perform is in accelerating the washing machine tub from a standing start to high speed spin, the tub being filled with water and clothing. This job requires motors which need heavier windings and more insulation to effectively accommodate the heat produced in such acceleration. lt is the purpose of this'invention to overcome this ditliculty by preventing an acceleration of the tub and motor from zero to high speed in one operation and by taking advantage of a lower gear ratio during such acceleration from a standing start.

Accordingly it is an object of this invention to provide a control cycle for an automatic washing machine which will prevent a spinning operation while the fabric to be spun is above a predetermined temperature.

It is also an object of this invention to provide a control cycle for an automatic washing machine which will prevent the initiation of a high speed spin for a delayed period.

It is a more particular object of this invention to include a thermostatic device in series control of the spinning mechanism to delay the operation thereof until the temperature of the fabric sensed by such device has reached a predetermined temperature.

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It is also a more specific object of this invention to include a delay device in the high speed spin circuit of a washing machine to insure that a high speed spin will be preceded by a low speed spin.

Further objects and advantages of the present invention will be apparent from the following description, reference being had to the accompanying drawings, wherein a preferred form of the present invention is clearly shown.

In the drawings:

FIGURE 1 is a fragmentary sectional view of a clothes washing machine suitable for use with this invention;

FIGURE 2 is an elevational View of a washing machine control panel provided with the teachings of this invention;

FIGURE 3 is a detailed view of the timer dial illustrated generally in FIGURE 2;

FIGURE 4 is a schematic wiring diagram for controlling an automatic washing machine in accordance with the concepts of this invention;

FIGURE 5 is a timer cycle chart showing the open or closed condition of the identically numbered timer contacts in FIGURE 4;

FIGURE 6 is a perspective view of a high speed spin solenoid and switch combination utilized in accordance with this invention; and

FIGURE 7 is a fragmentary view of the control panel shown in FIGURE 2 and illustrating the spin temperature control means for different fabrics.

In accordance with this invention and with reference to FIGURE 1, a clothes washer 50 having a clothes loading door or lid 51 is adapted to include a rotatably mounted spin basket 52 and an agitator 54 therein. An agitating and spinning mechanism, shown generally at 56, is utilized to vertically reciprocate the agitator 54 when a rotatable housing portion 58 is rotated in :one direction, and to rotate the spin tub 52 in a centrifuging operation when the housing 58 is rotated in a reverse manner. This agitating and spinning mechanism 56 is more fully taught in the patent to Sisson 2,758,685 issued August 14, 1956, and in a copending application to Sisson Ser. No. 738,362 filed May 28, 1958, now Patent 2,987,904 issued June 13, 1961, for an improvement to the Sisson mechaism. A prime mover 60 may be four-pole, six-pole, twospeed reversible motor adapted to rotate selectively the mechanism housing portion S8 through a belt-and-pulley arrangement, shown generally at 62. More specifically, the motor 60 is provided with a shaft 64 on which are relatively rotatably mounted a small agitate/spin drive pulley 66 and a larger spin drive pulley 68. A selector clutch 70 is interposed between pulleys 66 and 68 and keyed against relative rotation to the shaft 64, but with relative axial movement permitted. A yoke 72 is piv-oted on a bracket 74 by a high speed spin solenoid or tub spin speed control means 76. When the solenoid 76 is de-energized, the selector clutch 70 is biased downwardly and is effective to transmit rotational motion from shaft 64 to the pulley 66. The energization of solenoid 76 causes clutch 70 to engagngly drive pulley 68.

With the motor in a six-pole arrangement and thus operating in low speed, the pulley 66 will effect a slow speed agitation by rotating housing 58 through a driven pulley 78 aiiixed thereto and a V-belt 80. With the motor 60 still energized for low speed operation, but in reversed fashion, the pulley 66 will drive pulley 78 to rotate housing 58 in effecting a slow speed spin of tub 52. Fast reciprocation of agitator 54 is accomplished in a fourpole motor arrangement for operation of motor 60, still driving housing 58 through pulley 66 with solenoid 76 de-energized. Driving pulley 68 is selected by clutch 70 solely'for high spin operation when solenoid 76 is energized to lift yoke 72 and engage clutch 70 with driving pulley 68. Thus, a high speed spinning or centrifuging operation is effected by way of motor shaft 64, selector clutch 70, driving pulley 68, V-belt 82 and driven pulley 84. For the purposes of this application, the foregoing description is believed to suffice. However, for a more complete disclosure of the components for this multispeed driving arrangement, reference may be had to a copending application to Sisson, et al., Ser. No. 738,330 filed May 28, 1958, now Patent 2,974,542 issued March 14, 1961.

The motor 60 is provided with a four-pole start or phase winding 86, a fast speed four-pole main winding 88 and a slow speed six-pole main winding 90 (FIGURE 4). The mot-or 60 includes also a centrifugal switch 92 operable in conventional manner to drop out the phase Winding 86 after the motor 60 has accelerated to a predetermined percentage of the selected running speed.

Surrounding the spin tub 52 and spaced therefrom is a water container 94 mounted to the outer casing of the washing machine 50 by brackets 96. A partition or bulkhead 98 closes the lower open end of the water container 94, thereby to separate in water-tight fashion the watercontaining area above partition 98 from the driving mechanism disposed therebelow. Water is supplied to the interior of tub 52 through a hot Water valve 100 actuated by a hot water solenoid 102 and a cold water valve 104 actuated by a cold water solenoid 106 (FIGURES l and 4). A mixing conduit 108 carries the tub water fill at a temperature determined by the positioning of water valves 100 and 104 to a water chute 110 overlying the top opening of spin tub 52. The spin tub, in conventional fashion, is provided with a plurality of outlets 112 for exhausting water therefrom during each spinning operation of the tub. A drain conduit 114 selectively removes the Water collecting above the partition 98 in accordance with the operation of a pump 116 disposed at the end of and operated by motor shaft 64.

Reference may now be had to FIGURE 2 wherein a view of the console or control panel 118 is illustrated. The control panel 118 includes a fabric wash selection portion 120 controlled by a knob 122 adapted to select a first position 124 for Regular White fabrics, a second position 126 for Regular Colored fabrics, a third position 128 for Wash-and-Wear fabrics, a fourth position 130 for Delicate fabrics, and a fifth position 132 for other Special fabrics. The rotation of knob 122 will locate an indicator 123 in one of these five positions to actuate each of five separate switches, namely, a rinse Water temperature selector `switch blade 134, a wash water temperature selector switch blade 136, an agitate speed selector switch blade 138, a spin speed selector switch blade 140 and a timer speed or cycle selector switch blade 142. The cycle switch is included to vary the duration of the agitation periods and the spin periods during the wash cycle. This is accomplished by shifting gears in a two-speed timer so that a 60-second escapement period or pulse is established for a Normal cycle and a 40-second pulse for a Short cycle. The wiring diagram in FIGURE 4 illustrates the switches 134, 136, 138, 140 and 142 schematically as independent switch means, for purposes of clarity. However, it may be desirable to incorporate the desired simultaneous positioning of all live switches (those switches enclosed by a single dashed line box) to a particular wash program in accordance with the single selection at knob 122 of a particular fabric, such as indicated by positions 124, 126, 128, 130 and 132.

The rinse selector switch 134, when closing a circuit with a warm rinse contact 144, provides for warm rinse' water during the rinse portion of the washing cycle. An open switch 134 deenergizes solenoid 102, and a cold rinse results. The wash selector switch 136, when closed on a warm wash contact 146, effects a wann wash solution, and when switch 136 is open, a hot wash solution. The agitate speed switch 138 may be selectively positioned on contact 148 for a fast agitate of 330 pulsations or reciprocations per minute (P.P.M.) and effects a slow agitation of 220 P.P.M. when residing on a contact 150. The spin selector switch blade 140 has an open position for a slow speed spin of 330 r.p.m. and a closed position on contact 152 for a fast spin of 850 r.p.m. The cycle switch blade 142 has a position on a contact 154 for normal timer speed operation and on a contact 156 for a short cycle or fast timer speed operation.

Research has determined the most satisfactory wash cycle for the particular fabric selections 124, 126, 128, and 132 and these cycles are set forth more particularly in a copending application to Sisson, et al., Ser. No. 784,412 filed July 14, 1958. For the purpose of this invention, it is necessary only to set forth the Wash-and- Wear cycle 128.

With Wash-and-Wear 128 selected on fabric selector 120, a short cycle will be effected with cycle switch blade 142 on contact 156; a warm water wash with wash selector blade 136 on contact 146; a cold water rinse with rinse selector blade 134 in open position; a fast agitate with agitate selector blade 138 on contact 148 and a low speed spin with spin selector blade in open position. It will be noted that the Wash-and-Wear cycle includes a low speed spin. This arrangement is helpful in minimizing the setting of wrinkles into the man-made fabrics as a result of the centrifuging. However, it has been found that the temperature of the fabrics at the time they are centrifuged has a primary bearing on the resultant wrinkling effect of the spin-dry operation. Controlling the temperature of the fabrics prior to spin has been found to be the answer to the Wrinkling problem and it is to this end that one aspect of this invention is directed.

The temperature of wet man-made fabric below which centrifuging will'not cause set-in wrinkles is called the threshold temperature. For each fabric this threshold temperature may be different. Therefore, if a control system is to be invented which will meet the needs of future fabrics, provision must be made for a variable temperature responsive system-a system which may be preset for the fabric to be washed and which will automatically prevent the spinning of such fabrics so long as the temperature of the fabric remains above its particular threshold temperature. Of course, it is conceivable that fabrics may be discovered which should not be spun when they are below a given temperature. The concepts of the temperature responsive system here to be described are believed equally applicable in either instance.

In accordance with this invention it is proposed to include a cold water overflow period at the end of the wash agitate period to cool off the wash water before starting the spin. This will prevent wrinkles from being set in the wash-and-wear material which would otherwise occur when such material is centrifuged While still warm. Specifically, at the beginning of the sixteenth timer advance, contacts 10 and 14 are closed by timer switches 220 and 218, respectively. Since the selection of Washand-Wear or 128 on the fabric selector 120 programs an open position for rinse temperature switch 134, the above sequential positioning of timer switches 220 and 218 will energize the cold water solenoid 106, only, for the cold water overflow. Solenoid 106 will thus be energized from L1, switches 210, 212, wash contact 3, timer switch 216, timer switch 218, rinse fill Contact 14, timer rinse feedback contact 10, timer switch 220 and solenoid 106 to L2.

In this manner, cold water is admitted to tub 52 through..V conduit 108 to dilute the warm water and thereby cool the fabric in the water before initiating spin to damp dry the fabric.

The admission of a cooling fluid to the tub 52 to lower the fabric temperature pri-or to spin is controlled as follows. A fabric spin temperature timer contact 22 is contained in the timer and acted upon by a fabric spin temperature timer switch blade 302. In cooperation with the contact 22 the timer includes a fabric temperature bypass contact acted upon by a by-pass or shunt switch blade 304. The timer is designed so that cont-act 20 is closed dur-ing all but the overflow period, timer advances 16 and 17 (see FIGURE 5), while contact 22 is closed during the overflow period only. In other words, contact 20 is open when conta-ct 22 is closed and vice versa. Since either contact 20 or contact 22 is in series wit-h a timer motor 185, one or the other of these switches 20, 304 or 22, 302 are in control of the energization of the timer motor. In series with the fabric temperature timer contact 22 is a fabric or spin temperature thermostat 306. The thermostat includes a switch blade 308 which cooperates with the timer switch 302 to close a circuit through the timer motor 185. The thermostat 306 is of the adjust-able type having a screw or lbellows 310 for permitting selective adjustment of the thermostat to the desired spin temperature as will be described more fully next following. A temperature sensitive element 307 operating through the bellows 310 is placed in a position where it Will predict most accurately the temperature of the fabrics prior to spin. In this arrangement the element 307 is placed on the Ibulkhead 98 adjacent the drain opening 309. Thus, as water is overiiowed from the tub 52 by way of ports 112, the temperature thereof, and consequently the temperature of the fabric in the tub 52 will be accurately sensed as the water flows to drain.

As aforesaid, it h-as been determined that different fabrics have different threshold temperatures, spinning above which sets in wrinkles. This invention seeks to overcome this variable problem by controlling the centrifuging or spinning in accordance with the yfabric being washed. Reference may be had to FIGURE 7 where a fragment-ary portion of the control panel in FIGURE 2 is shown. A knob 312 is inclu-ded for selecting the particular manmade fabric to be washed, in this instance and by way of example only, Orlon, Daeron, nylon and rayon. This control could, of course, be adapted to an indefinite number of fabric types presently available or to be developed in the future. The knob 312 is connected to the adjustable thermostat element 310 and designed to preset the thermostat so that a spinning process will not be initiated until the temperature of the fabric to be spun has reached the desired setting as programmed by knob 312. The knob 312 may be of the push-pull on-oif switch type so that the thermostatic switch blade 308 will be closed pos-itively in those instances where regular clothing is being washed which is not affected by spinning above any given temperature. This in effect locks the thermostat 306 out of circuit control by providing a closed circuit through the thermostat.

The washing machine control panel of FIGURE 2 includes also a timer dial, shown generally at 160. A knob 162 is centered on the dial 160 and acts to rotate an indicating arm 164 behind an arcuate opening 166 which is partitioned to indi-cate segments of the washing cycle. Reference may be had to FIGURE 3 for greater detail on the timer dial characteristics and an illustration of the control sequence obtained through the improved washing machine .set forth herein. To initiate a wash period, the operator may rotate the indicating arm 164 to a desired'position behind one of the windows 168 which are indicative of the wash agitation portion of the wash cycle. In accordance with the position of the indi-cator 164 behind the windows labeled Heavy, Norm and Light, the operator will secure the desired length of agitation. yThis flexibility permits the operator to take into account the degree of soil of the clothes being washed, a longer agitation period being necessary for the more soiled fabric. =Of course, a wash full period will precede the agitation at which time the selected amount of water will be introduced to tub 52 in accordance with a load selector control to be described more fully hereinafter. The Lint Away Wash is indicative of that portion of the cycle near the end of the agitation period where water is admitted to the spin tub 52 in a manner to cause overow through tub outlet ports 112, thereby to float away that scum and lint collecting on the surface of the water and to selectively cool the fabric as described hereinabove. The Spin is self-explanatory and indicates merely the centrifuging of wash water from the fabrics being processed after the fabrics have been cooled. Thus, the therm-ostat 306 will initiate the spin. The Fill indicates that portion of the cycle during which water is admitted to the tub 52 for rinsing and also the agitation that accompanies the rinsing process. Lint Away Rinse is that section of the washing cycle, similar to the Lint Away Wash, wherein water is overflowed through tub ports 112 near the conclusion of the rinsing process to carry oif lint and scum collecting on the surface of the rinse water. For additional details of the washing cycle shown in the 'drawings and programmed in FIGURE 2, reference may be had to the aforesaid copending application Ser. No. 748,412, now Patent 2,976,710 issued March 28, 1961.

In operation, the user of a washing machine 50 provided with this invention may rai-se the lid 51 and place within the tub 52 a quantity of fabrics or clothing, the spinning temperature of which is critical if wrinkling is to be eliminated. The user will select the Wash-and- Wear cycle 128 by positioning indicator 123 for such operation by knob 122. To insure a temperature responsive centrifuging operation, the operator will then preset knob 312 to the particular fabric being washed. The dial in FIGURE 7 is shown including four presently known man-made fabrics but lsuch control may include others as required. As aforesaid, one position of the knob 312 may lock switch blade 308 closed to eliminate this thermostatic control feature.

The knob 312 will be thus placed in condition to actuate the thermostatic sensing device 306. In a conventional manner a timer knob 162 will be positioned to initiate a washing cycle as more fully taught in copending application Ser. No. 748,412 filed July 14, 1958, now Patent 2,976,710 issued March 28, 1961. Water at the selected temperature will be introduced to tub 52 and an agitating cycle will follow wherein the fabric is cleaned. Near the end point of the agitation, the sixteenth and seventeenth advance on the timer cycle chart of FIGURE 5, contacts 10 and 14 (FIGURE 4), will be closed to initiate an overflow period. At this time, cold water is introduced through the energization of solenoid 106 to the tub 52. The water level will rise until it overflows through ports 112 into the chamber located immediately above the bulkhead 98 and will consequently ow to drain through the drain opening 309. In so doing, the thermostatic sensing element 307 will sense the temperature of the water being removed or overflowed from the tub 52. Since the fabric within the tube will have the same temperature as the water therein, the element 307 will in effect be sensing the fabric temperature as well. In accordance with the teachings of this invention, the overiiow period is placed under the control of timer switch contacts 20 and 22 as seen -in the timer cycle chart of FIGURE 5. The timer switch 304 is opened to open contact 20 at the beginning of the sixteenth timer advance. Simultaneously therewith timer contact 22 is closed by timer switch 302. Thus, the timer motor which had been energized in series with timer contact 20 at the beginning of the washing cycle is now placed under the control of timer contact 22 and its associated switch 302. In series with contact 22, however, is a thermostatic device 306 through which the fabric temperature sensing element 307 works. Let us assume that the overflow period has just been initiated at the beginning of the sixteenth timer advance. The water being overflowed to the drain opening 309 will be comparatively warm, the element 307 sensing this condition and holding the thermostatic switch 308 in an open position. Since timer switch 20, 304 is opened as well as the switch blade 308 in the `thermostat 306, the timer motor 185 will be deenergized and the entire operational cycle of the washing machine will be placed under the control of the thermostatic device 306. As more cold water is introduced through conduit 108 to the tub 52, the temperature of the water being overtlowed, 4and consequently the fabric in said water, will be decreased to a point at which the sensing element 307 closes switch 308 to reenergize the timer motor 185. With the timer motor again energized, the timer switches will be sequentially positioned in accordance with the programmed washing cycle of FIGURE 5. The first advance after the fabric has reached the desired temperature and the timer motor is again energized, the timer switch 304 will be closed and the timer switch 302 opened to effectively by-pass the thermostatic device for the remainder of the washing cycle. The final spin in the Washing cycle as shown in FIGURE 5 need not have the thermostatic control over the fabric to be spun since the water within the tub 52 just prior to the second spin is programmed as cold. Of course, it is within the purview of this invention to place the thermostatic device 306 in control of the spinning operation wherever needed, simply by appropriately positioning the timer switches 20, 304 and 22, 302 at the desired point in the timer cycle. It should now be seen that an arrangement has been provided whereby the fabric being washed is centrifuged only at that temperature found most desirable to prevent wrinkles from being set -into the fabric. The adjustable nature of the thermostat 306 effects this operation in accordance with the preselection by the user on knob 312.

One other feature of the improved circuit includes a spin operation which always starts in a low 330 r.p.m. tub speed until the second timer pulse interval of the spin cycle. Thus, at the beginning of the spin period which is initiated shortly after the start of the eighteenth timer advance, the spin cycle will be initiated at a slow speed of 330 r.p.m. for spinning the tub 52 in removing most of the water therefrom. This one timer interval delay permits most of the water to be spun from the tub 52 before initiating high speed spin, thereby minimizing the strain on the motor 60. At the nineteenth timer advance, the timer contact 13 is closed to place the spin speed selector in the circuit and the spin speed will be determined by the positioning of the spin selector switch blade 140. If closed on fast spin contact 152, the spin solenoid 76 will be energized to lift the shifter fork 72 and thus the selector clutch into engagement with drive pulley 68, thereby accelerating tub 52 to a fast or 850 r.p.m. spin. Without the energization of solenoid 76, the spin will remain 330 r.p.m., the motor shaft 64 driving pulley 66 through the selector clutch 70 and thus rotating the mechanism housing 58 by way of driven pulley 78. Since the speed change ratio is greater in transmitting power from motor 60 through large pulley 68 to the rotatable housing 58 than through the smaller pulley 66, it would appear desirable to accelerate t-he tub 52 through the most advantageous ratio, i.e., through pulley 66. This too is accomplished by always preceding high speed spin with low speed spin. It should be noted that a more particular description of the prime moving arrangement for rotating the mechanism 56 in either a spin direction or an agitate direction is more fully taught in the copending application Ser. No. 738,330, Patent 2,974,542, cited hereinbefore.

This aspect of the invention is directed to providing an operational cycle which will insure that a high speed spinning operation will be started in or preceded by low 8 speed spin. As seen in the timer cycle chart of FIGURE 5, the timer contact 11 is closed at the beginning of the eighteenth timer advance and the motor 60 is energized to effect a low speed spinning operation, the clutch 70 being dogged to pulley 66. One timer advance later or at the beginning of the nineteenth timer interval, contact 13 will be closed by timer switch 218 to energize the spin circuit. Under normal operation where the washing cycle is permitted to proceed normally from start to finish, the delay of one timer advance is always included to permit the tub 52 to spin rst in low speed until most of the water is spun from the tub by means of ports 112. Thereafter, when contact 13 is closed, the spin circuit is energized for high speed spin, the solenoid 76 is energized to lift the clutch 70 into driving engagement with high `speed spin pulley 68 and the tub 52 and the clothing therein are spun at such speed. However, there are certain ways in which the operator may avoid this built-in timer delay and it is to this potentiality that one aspect of the present invention relates.

One situation in which the operator could avoid the one timer advance delay of high speed spin is to open the lid 51 during high speed spin, i.e., when the spin speed selector switch blade is closed on contact 152. When the lid 51 is open, lid switch 214 is opened as well. This lid opening will deenergize the motor 60 and cause the tub 52 to coast to a stop. Thus, the reclosing of the lid 51 and, consequently, the lid sw-itoh 214 will set up an immediate energization of the prime moving means for high speed spin. With reference to FIGURE l, high speed spin is accomplished by the energization of solenoid 76 which lifts the clutch 70 by means of yok'e 72 into frictional driving engagement with the drive pulley 68. In this fashion driven pulley 84 aiiiXed to the mechanism housing 58 is rotated at high speed, thereby imparting a high speed spin to the tub 52., Accelerating tub 52 from zero r.p.m. to 850 r.p.m..

imparts severe strain to the motor 60 and requires additional insulation on the windings thereof to offset the added heat -loss from such rapid acceleration Another means by which the luser may avoid the high speed spin delay built into the timer cycle is to manually advance the timer dial 162 through the eighteenth timer advance which is designed into the timer cycle as a high speed spin delay. To so do causes the prime moving means to be energized immediately for high speed spin.-

The addition of a delay means to the high speed spin circuit in accordance with the teachings of this invention.

overcomes both of these operational possibilities and msures that a low speed spin will always precede a spin of high speed.

With reference to FIGURE 4, the high speed spinV type shown in the patent to Werner 2,242,769 issued May 20, 1941, and adapted to close a circuit therethrough after approximately ten seconds. time for the driving mechanism to rotate the tub 52 in low speed spin before the solenoid 76 is energized. For purposes of clarity low speed spin may be described with reference to FIGURE 1 wherein the deenergization of high speed solenoid 76 permits the dogged engagement of clutch 70 with drive pulley 66, thereby driving the rotatable housing 58 of the agitate and spinning mechanism 56 to effect a low speed spin of the tub 52. The timey delay device 324 may include a hot wire or a bimetallic clement 326 which is effective after a predetermined This delay provides period to close a set of internal contacts 323, 330 within the delay device 324. A resistor 332 may be included in series with the delay device 324 and in parallel with the contacts 328, 330 so that the time delay of the device may be properly adjusted-an increase in resistance of the element 332 serving to lengthen the delay` The fact that the resistor 332 is in seri-es with the solenoid 76 limits the voltage across the solenoid and prevents the actuation of the latter. The resistance should be sized to limit the voltage across the solenoid to one-third the normal solenoid operating voltage. Thus, the energization of the prime moving means for high speed spin will first close a circuit through the time delay device 324 and prevent the energization of solenoid 76 until a predetermined period thereafter at which time the contacts 328 and 33t) close. At this time the solenoid 76 will be energized to ilift the yoke 72 in causing the clutch 70 to engage the high speed spin pulley 68. In this manner, the tub 52 will be accelerated to high speed spin only from a low speed spin rather than from a dead start. Further, this will reduce the temperatures at which the motor 60 is required to operate and permit the use of a smaller motor.

Since heat must be dissipated by the relay device 324 whenever the high speed spin circuit is energized, yit is desirable to remove the device 324 from the spin circuit whenever the solenoid 76 is energized. For this purpose solenoid 76 may include a switch actuator button 340 which projects through the core of the solenoid and extends toward a switch 342. Thus, the energization of the solenoid 76 will cause the armature 344 thereof to raise, thereby push-ing the actuator button 346 upwardly into actuating engagement with the switch 342. The closing of switch 342 will shunt the time delay device 324 out of the spin c-ircuit and thus eliminate the continuous heat loss which would arise should the delay device 324 remain in series with the high speed spin solenoid 76 throughout the spinning operation. Of course, it is within the purview of this invention to place the switch 342 at the other end of the solenoid 76, such that the lifting of the armature 344 will close the switch 342.

The high speed spin circuit is thus comprised of a delay circuit and a delay by-pass circuit. Whenever the lid v switch 214 is actuated by the opening and closing of the washer lid 51 during high speed spin and/or whenever the time delay will be provided as follows. The motor through the eighteenth on twenty-eighth timer advance (the high speed spin delay intervals built into the timer) the time delay will be provided as follows. The motor 60 will be energized to rotate the agitate and spinning mechanism 56 through driving pulley 66. At the same time, the high speed spin circuit will be energized from L1, safety switches 210, 212, line 246, fl-id switch 214, timer switch 224, line 248, line 238, timer switch 218, timer contact 13, line 320, line 346, time delay device 324, line 348, spin speed selector switch 140, high speed spin solenoid 76, line 322 to L2. After a predetermined period, the delay contacts 328, 33t) will close and the high speed spin solenoid 76 will tbe energized to raise the clutch 70; with the actuation of the solenoid 76 switch 342 will be closed to by-pass the time delay device 324 and high speed spin will be continued with the motor 60 driving the agitate and spinning mechanism 56 through drive pulley 68.

It should now be seen that a completely safe circuit arrangement has been provided for high speed spin. Regardless of the users operation of the washing machine 50, the prime moving means including the motor 60, the clutch 70', and the selected belt and pulley arrangement 62 will always be conditioned for a low speed spin prior to high speed. This takes advantage of the best pulley speed changing ratio during the initial acceleration of the tub 52 and, further, permits adaptation of a less expensive motor to a multi-speed operation.

While the form of embodiment of the invention as herein disclosed constitutes a preferred form, it is to be understood that other forms might be adopted, as may come within the scope of the claims which follow.

What is claimed is as follows:

1. A speed control arrangement for an appliance having a tub comprising, prime moving means for rotating said tub at high and low speed and including tub speed control means energizable for effecting rotation of said tub at said high speed and deenergizable for effecting rotation of said tub at low speed, a speed selector switch connected to said tub speed control means and closable for conditioning said tub speed control means for energization to effect rotation of said tub at high speed and delay means for said prime moving means to insure tub rotation is initiated only at said low speed, said delay means including a thermally responsive switch closing means in series with said speed selector switch and said tube speed control means and selectively energizable for energizing said tub speed control means when said speed selector switch is closed to effect rotation of said tub at said high speed after a predetermined time interval of rotation of said tub at said low speed.

2. The speed control arrangement of claim 1 including a resistance means in parallel with said thermally responsive switch closing means and in series with said speed selector switch and said tub speed control means for controlling the duration of said predetermined time interval.

3. The speed control arrangement of claim 2 including means responsive to the energization of said tub speed control means for by-passing said delay means at the end of said predetermined time interval.

4. A speed control arrangement for an appliance having a tub comprising, prime moving means for rotating said tube at high and low speed and including tub speed control means selectively energizable for effecting rotation of said tub at said high speed and for effecting rotation of said tub at low speed, and delay means for said prime moving means to insure tub rotation is initiated only at said low speed, said delay means including a thermally responsive switch closing means connected to said tub speed control means and selectively energizable for controlling said tub speed control means to effect rotation of said tub at said high speed after a predetermined time interval of rotation of said tub at said low speed.

5. The speed control arrangement of claim 4 wherein said thermally responsive switch closing means includes a relatively fixed contact, a relatively movable contact, a thermally responsive element connected to said movable contact for moving said relatively movable contact into engagement with said relatively fixed contact when heated and resistance means selectively energizable with said delay means and in heat transfer relationship to said thermally responsive element.

6. A control circuit for a rotatable container having a prime moving means including a motor for rotating said container at high and low speeds and comprising, means energizable for conditioning said prime moving means for high speed rotation of said container, a power supply, a high speed circuit connected to said power supply and including in series power supply relationship a first timer switch means closable to energize said high speed circuit, a speed selector switch means settable for high or low container rotation speed, a thermal time delay switch closing means and a high speed conditioning means, and second timer switch means closable with said first timer .swithc means for energizing said motor, said first timer switch means energizing said thermal delay device to delay energization of said high speed conditioning means when said speed selector switch means is set for high container rotation speed.

7. The control circuit of claim 6 including a resistance means in parallel with said thermal time delay switch 11 closing means and in series with said rst timer switch means and said speed selector switch means for controlling the duration of said delay before energization of said high speed conditioning means.

References Cited by the Examiner UNITED STATES PATENTS Holmes 317-141 Raver 318-305 Knight 210-138 X Dunlap 210-144 X Alexander et al. 210-138 Long et a1. 68-12 REUBEN FRIEDMAN, Primary Examiner.

HERBERT L. MARTIN, CHARLES SUKALO,

Examiners. 

6. A CONTROL CIRCUIT FOR A ROTATABLE CONTAINER HAVING A PRIME MOVING MEANS INCLUDING A MOTOR FOR ROTATING SAID CONTAINER AT HIGH AND LOW SPEEDS AND COMPRISING, MEANS ENERGIZABLE FOR CONDITIONING SAID PRIME MOVING MEANS FOR HIGH SPEED ROTATION OF SAID CONTAINER, A POWER SUPPLY, A HIGH SPEED CIRCUIT CONNECTED TO SAID POWER SUPPLY AND INCLUDING IN SERIES POWER SUPPLY RELATIONSHIP A FIRST TIMER SWITCH MEANS CLOSABLE TO ENERGIZE SAID HIGH SPEED CIRCUIT, A SPEED SELECTOR SWITCH MEANS SETTABLE FOR HIGH OR LOW CONTAINER ROTATION SPEED, A THERMAL TIME DELAY SWITCH CLOSING MEANS AND A HIGH SPEED CONDITIONING MEANS, AND SECOND TIMER SWITCH MEANS CLOSABLE WITH SAID FIRST TIMER SWITCH MEANS FOR ENERGIZING SID MOTOR, SAID FIRST TIMER SWITCH MEANS ENERGIZING SAID THERMAL DELAY DEVICE TO DELAY ENERGIZATION OF SAID HIGH SPEED CONDITIONING MEANS WHEN SAID SPEED SELECTOR SWITCH MEANS IS SET FOR HIGH CONTAINER ROTATION SPEED. 